For future reference, this can all be found in the course calendar (which can be accessed by googling mcmaster course calendar). Also keep in mind that this is the information for THIS year, but it can change from year to year.
For Psych 1X03: grade 12 biology or the equivalent university course (bio 1P03) are recommended but not required.
For Psych 1XX3: based on the way the course calendar is written, it sounds like students in Arts & Science do not need biology in order to take this course, which I find odd, since it is the one that is more based on biology.
For Bio 1M03: grade 12 biology or bio 1P03 is required
For Bio 1A03: Same thing as psych 1XX3, and I find that even stranger, since it is cell biology and probably the one that draws most on material learned in grade 12 biology - however, students in arts & sciences as well as some engineering programs don't require grade 12 biology.
If you're interested in bio and psych, it would be a good idea to take it.
Many upper-year courses in bio and psych require both of the first-year courses, and it will probably make your life easier in the first-year courses.